This invention relates to a seat belt safety system for automobiles. More particularly, this invention is directed to a seat belt system that promotes and ensures proper seat belt usage of a vehicle occupants by making sure that the vehicle does not move until all occupants of the vehicle are properly secured in their seats.
Prior to the present invention, there have been many proposed systems for assuring that occupants in vehicles are secured therein. In most industrial nations that produce vehicles, laws have been passed to ensure that the manufacturers provide safety equipment in vehicles that protect the occupants. With such governmental requirements and public insistence on protection in vehicles, many patents have attempted to provide a system that will adequately protect the occupants in the vehicle without incurring overbearing expense to the manufacturer and yet be practical and user friendly so that the occupants will use the system and not try to bypass it.
U.S. Pat. No. 3,438,455 (Redmond) discloses a mechanical interlock system for the gear selector control that is positively applied by a spring and retracted by electro-mechanical means. U.S. Pat. No. 3,859,625 (Eggert) discloses a mechanical interlock system for the travel control means which is independent of the ignition system, after first engerization, and which is of the fail-safe type in which the interlock is normally positively retracted, as by a spring, and extended by electromechanical means when a seat is occupied and yet the belt unfastened. U.S. Pat. No. 3,870,120 (Blinkilde) discloses a transmission locking apparatus that is capable of being accommodated within the tubular shroud of a steering column assembly. This apparatus is composed of a solenoid having a first coil operable to drive a gear selector lever locking member to its lock position when the engine starting mechanism is energized and a second coil is operable to maintain the locking member in the lever-locking position until the driver""s body restraining belt is fastened, whereupon the locking member is restored to its non-lock position to enable the gear selector lever to be adjusted to a drive mode.
Although these prior art systems may have solved the safety problems of occupants in the past, with today""s many state-of-the-art technological innovations of vehicles and the need to conserve space and weight, they do not meet the new requirements. Hence, there still is a need for smart, economical, and efficient systems that are compatible with today""s state-of-the-art technological vehicles.
The present invention is directed to a seat belt shifter lock (hereinafter referred to as xe2x80x9cSBSLxe2x80x9d) microprocessor system for use with a vehicle having an automatic transmission for preventing the shifting from park position into a moving position of the vehicle until driver and all passengers are properly secured into their seats and the driver depresses the brake.
More specifically, in a safety seat belt system for use with a motor vehicle having an engine ignition system, drive train means including PRNDL control means therefor shiftable between an engine starting position and at least one drive position for transmitting power from the vehicle engine to the vehicle drive wheels, hazard light means, safety seat belt means for releasably securing the operator to the driver""s seat of the vehicle and at least one other safety seat belt means for releasably securing at least one passenger to at least one passenger""s seat of the vehicle, said safety seat belt means each including a pair of separable seat belt sections, the sections of each pair being adapted to be releasably connected together and providing an electrical circuit through at least one section of the pair when connected, the improvement comprising inserting a seat belt shifter lock (SBSL) control means into the vehicle""s wiring circuitry for controlling the movement of the vehicle which is started when ignition voltage is detected in the vehicle by the SBSL control means, signals from the PRNDL switch, seat belt switches, at least one passenger seat sensor means, and brake switch are processed and the SBSL control means sends a signal to the shifter lock solenoid to let the vehicle be placed in a movement gear if all occupants of the vehicle are properly restrained in the seats or to prevent movement of the vehicle if the seat belt of the driver or any passenger is unfastened